부산대학교 도서관

In this paper, we present an antenna cluster concept operating in millimeter-wave (mm-Wave) frequency bands for 5G applications. Unlike conventional arrays made up of identical elements, a cluster array is constructed using non-identical dipoles with high coupling that are placed in a 2-mm wide slot. The cumulative distribution function (CDF) of the spherical coverage gain is used to evaluate the beam-forming capability. High coverage gain over a wide band can be achieved by adjusting the amplitudes and phases of excitation vector. To further enhance the spherical coverage, reactive elements are loaded into the gaps between adjacent dipoles. These reactive elements are selected from a pre-defined database using genetic algorithm-based optimization. The proposed connected dipole cluster demonstrates hemispherical coverage gains greater than 4 dB in the low band (24 to 29.5 GHz) and greater than 6 dB in the high band (37.5 to 43.5 GHz) at the 50%-tile CDF.